Operational Acceptance Test (OAT) Manager

The Operational Acceptance Test (OAT) Manager is responsible for ensuring that refreshed or modernised infrastructure platforms are fully operationally ready before transition into live service. The role provides assurance that infrastructure changes - including hardware, networks, operating systems, cloud platforms, and core services - can be supported, monitored, secured, and operated with minimal risk to business services. Working closely with infrastructure delivery teams, service management, and operations, the OAT Manager ensures that operational acceptance is achieved without disrupting existing services during migration, cutover, or coexistence phases.

Key Responsibilities

OAT Strategy & Planning

Define and own the Operational Acceptance Test strategy for the infrastructure refresh programme

Develop OAT plans aligned to phased migrations, cutovers, and rollout waves

Ensure OAT activities cover both new infrastructure and impacts to existing live services

Establish clear OAT entry and exit criteria appropriate to infrastructure change

Infrastructure Service Readiness

Coordinate and manage OAT activities across compute, storage, network, and end-user computing platforms

Validate monitoring, alerting, capacity management, and operational tooling

Ensure backup, recovery, disaster recovery, and resilience controls are tested and evidenced

Validate security controls, access management, patching, and vulnerability management

Transition, Migration & Cutover Support

Support infrastructure migration and cutover activities by ensuring operational controls are in place

Validate rollback, recovery, and coexistence procedures

Ensure operational teams are prepared to support both Legacy and refreshed infrastructure during transition

Provide OAT assurance to support go-live, migration, and decommissioning decisions

Stakeholder & Operational Engagement

Act as the primary OAT interface between infrastructure delivery teams, IT operations, and service management

Engage third-party suppliers and managed service providers as required

Facilitate service readiness workshops and operational walkthroughs

Ensure runbooks, support models, and escalation paths are complete and approved

Governance, Risk & Reporting

Identify, manage, and report operational risks related to infrastructure change

Ensure OAT outcomes are clearly evidenced and traceable

Provide regular status reporting on operational readiness to programme and senior stakeholders

Support formal OAT sign-off or readiness recommendations

Skills & Experience

Essential

Strong experience managing Operational Acceptance Testing or Service Readiness for infrastructure programmes

Proven experience with on-prem, cloud, or hybrid infrastructure platforms

Solid understanding of IT service management (ITIL) and live service operations

Experience supporting migrations, cutovers, and large-scale technology refreshes

Excellent stakeholder management and communication skills

Desirable

Experience in data centre exit, cloud migration, or infrastructure modernisation programmes

Knowledge of resilience, disaster recovery, and high-availability design

Experience working with third-party infrastructure providers or MSPs

Familiarity with SmartIT/Remedy, monitoring platforms, or CMDB tools

Qualifications

ITIL Foundation or higher (preferred)

Infrastructure or service management certifications (desirable)